A 37-year-old woman was diagnosed with chronic phase
chronic myeloid leukemia.
Nilotinib treatment was initiated; however, it had to be discontinued due to an
allergic reaction one month later, and
dasatinib treatment was provided. Although favorable response was obtained, she started complaining of
shortness of breath 7 months after initiating
dasatinib treatment. Chest X-ray and echocardiography indicated pulmonary congestion and
hypertension. Further, she was diagnosed with
mixed connective tissue disease (
MCTD) based on
Raynaud phenomenon, swollen fingers, sclerodactyly,
pancytopenia, hypocomplementemia, and positive anti-U1-RNP antibody. Consequently,
dasatinib treatment was discontinued, and she was administered
prednisolone (1 mg/kg/day), which was effective and successfully tapered with concomitant administration of
cyclophosphamide. This is the first case of
MCTD that developed during
dasatinib treatment. However, because the present case was a young woman, the development of
MCTD could probably be attributed to autoimmune
diatheses or it may be a coincidence. However, the possibility of patients receiving
dasatinib treatment developing
autoimmune diseases needs to be assessed.